The VRX918SP is a powered, suspendable subwoofer system containing a 2268FF neodymium magnet, patented Differential Drive®, 18" woofer in a front-loaded, vented enclosure. The VRX918SP was designed specifically for use in arrays with the VRX932LAP Line Array speaker and VRX-AF Array Frame. In addition it may also be used in arrays consisting entirely of VRX918SP subwoofers.